Binder clamp attachment for paper cutting machines



May 15, 1956 BINDER CLAMP ATTACHMENT FOR PAPER CUTTING MACHINES Filed Dec. l, 1953 IN V EN TOR.

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MMM U 2 m c A U uw W United States Patent O BINDER CLAMP ATTACHMENT FOR PAPER CUTTING MACHINES William C. Rupp, Parma, Ohio, assignor to The Chandler ahPrice Company, Cleveland, Ohio, a corporation of Application December 1, 1953, Serial No. 395,413

7 Claims. (Cl. 164-52) This invention relates as indicated to a novel binder clamp attachment for paper cutting machines, and more particularly to a special form of false plate adapted to be temporarily secured to the underside of the binder clamp.

The general construction of paper cutting machines and ,binder clamps forming a part thereof is well known in the art, and reference may be had to my prior Patents Nos. 2,633,195 and 2,633,219 showing and describing certain preferred forms of operating mechanism and also to McLaughlin Patent 2,608,254. The clamping member or foot of the clamp proper is ordinarily formed with a straight edge toward the front of the machine closely adjacent which the knife descends and with rearwardly protruding7 anges or fingers which bear upon the top of the stack of sheets over a considerable area and at the same time permit close approach of the usual movable back gauge which is provided with forwardly extending vertical flanges adapted to intert therewith. By this arrangement the clamping foot is adapted to bear heavily upon a relatively large area of the stack to compress and secure the same during the cutting operation and yet a rather narrow final cut may be made due to the permitted close approach of the back gauge anges to the front of such clamping foot.

When very thin paper stock is to be cut, however, such as a stack of onion skin sheets, such rearwardly extending anges or iingers of the binder clamp foot do not compress the material very satisfactorily since the latter tends to bulge therebetween, and a somewhat uneven and unsatisfactory cut may result. lt has accordingly been the practice, when dealing with materials of this nature, to secure a thin metal plate to the underside of the binder clamp foot bridging such rearwardly extending anges and alording a wide at area of Contact between the clamp and the stack. While this, of course, prevents such very close approach of the rear gauge, it does afford a much better clamping action on a stack of onion skin sheets or the like.

Modern paper cutting machines are designed for operation by a single operator standing at the front of the machine from which location he is able to advance or return the back gauge as desired, and to actuate the clamping and cutting mechanism. When shifting from one type of paper stock to another however, requiring the attachment or removal of such false plate, it has always been necessary for the operator to go around to the side or back of the machine and release the plate attaching means, ordinarily some form of nut and bolt or plunger latch. This has proved to be quite a nuisance and has detracted from etlicient operation of the machines.

It is accordingly a principal object of my invention to provide a novel binder clamp attachment for paper cutting machines and the like whereby such false plate may readily be secured to and removed from the underside of the clamping member from the front of the machine.

A further object is to provide such detachable false plate which is substantially automatically positioned and 2,745,489 Patented May 15, 1956 ICC securely retained against the underside of the binder clamp foot despite the rapidity and ease with which it may be put in place.

Other objects of the invention will appear as the description proceeds.

To the accomplishment of the foregoing and related ends, said invention then comprises the features hereinafter fully described and particularly pointed out in the claims, the following description and the annexed drawing setting forth in detail certain illustrative embodiments of the invention, these being indicative, however, of but a few of the various ways in which the, principle of thgjnvention may be employed.

ln said annexed drawing:

Fig. 1 is a vertical transverse section through the binder clamp, knife bar and table of a paper cutting machine;

Fig. 2 is an enlarged transverse section through the binder clamp foot and false plate secured thereto;

Fig. 3 is a horizontal transverse section along the lines 3 3 on Figs. 2 and 4;

Fig. 4 is a rear elevational view of a portion of the binder clamp and the false plate positioning and securing means; and

Fig. 5 is a top plan View of the false plate.

Referring now more particularly to such drawing and initially to Fig. 1 thereof, the embodiment of my invention there illustrated includes a stack supporting table 1 together with side frame members such as 2 having guideways therein for vertical reciprocation of the binder clamp 3 extending transversely of such table therebetween. A knife bar 4 mounting a knife 5 is positioned closely adjacent the front face of theY binder clamp for reciprocation by conventional operating mechanism (not shown).

In the form illustrated, the binder clamp 3 is suspended from cross-frame 6 by means of a vertical screw 7 threadedly engaging nut 8 held against rotation in the clamp member. The upper end of screw 7 is provided with a shouldered portion 9 holding the same against bodily downward movement and drive means may be provided in the form of a reversible electric motor 10 and gear reduction unit 11 engaging the upper end of screw 7 to rotate the same and thereby-raise and lower clamp 3. The particular form of drive mechanism employed is not a part of the present invention, and reference may be had to the several patents listed above for a more detailed description of the same.

My binder clamp foot is conventional in its general construction, being provided with a plurality of rearwardly projecting vertically extending anges 12 between which the forwardly projecting ingers of the back gauge (not shown) are adapted to intrude. The position of such back gauge may conveniently be indicated to the operator by means of a ruled tape 13 passing about a horizontal pulley 14 so as to be read at the front of the machine.

My new false plate or bottom plate 15 is of generally conventional dimensions, extending the length of the underside of the binder clamp foot and also rearwardly for substantially the length of anges 12. The exposed rear edge 16 is rounded whereas the front edge is adapted to continue the straight vertical line of the lower forward face 17 of the binder clamp foot. Two small cylindrical upstanding studs 18 and 19 project upwardly from plate 15 adjacent the two ends of the latter and are adapted to enter fairly closely fitting holes such as 20 in the undersides of corresponding anges 12, thereby properly to position and register such plate.

On plate 15 adjacent such respective studs 1S and 19 are two upstanding pins 21 and 22, each of which is located to project upwardly midway between two such anges 12 provided with spaced opposed cam surfaces having upwardly sloping portions 23 and 24 and terminating in raised horizontal portions 25 and 26.

Each such pin is provided with an enlarged base portion 27 serving as a lower stop for washer 28 mounted on the pin and normally resiliently held thereagainst by means of compression spring 29 interposed between such Ywasher and an adjusting nut 30.

It will thus be seen, with the foregoing description in mind, that my new false plate or bottom plate may readily be positioned and secured in place from the front of the machine (from the left as viewed in Figs. l and 2) as follows. With the binder clamp in elevated position, the operator reaches thereunder to bring plate rearwardly of and below the foot of the clamp 3. He then moves the plate 15 forwardly toward himself so as to engage each of the washers 28 with the respective sets of upwardly inclined cam surfaces 23 and 24. As he continues to move the plate 15 toward him, the springs 29 will be compressed, tending to draw the plate firmly against the underside of the clamp foot, but close engagement will be prevented until the studs 1S and 19 enter their corresponding holes such as in the underside of the foot. Such studs accordingly serve accurately to position the plate 15 and to prevent axial dislodgment of the same during use. The false plate 15 may likewise readily be removed by the operator from a position in front of the machine simply by reaching thereunder with his fingers and pulling down on the plate intermediate the flanges 12 to disengage the studs 18 and 19, whereupon the plate may be moved bodily rearwardly until clear of the binder clamp foot and then lowered and withdrawn to the front of the machine.

The novel false plate attachment of my invention accordingly greatly facilitates rapid and etiicient operation of the paper cutting machine without requiring the operator to step to the rear of the machine to attach, detach, or adjust the same. Despite the ease and rapidity with which such plate may be installed or removed, it is very firmly and accurately secured in place during use.

Other modes of applying the principle of the invention may be employed, change being made as regards the details described, provided the features stated in any of the following claims or the equivalent of such be employed.

I therefore particularly point out and distinctly claim as my invention:

l. In a paper cutting machine having a table, a binder clamp adapted to bear forcibly upon a stack of sheets on said table to hold the same rmly in position and compressed during the cutting operation, said clamp including a presser foot member having a continuous forward edge portion and a series of rearwardly protruding flange fingers adapted thus to bear on such stack, and a thin false plate adapted to be secured to the underside of said foot to bridge said lingers and therefore bear more uniformly on such stack; plate attaching means comprising upstanding studs on said plate adjacent the respective ends thereof, said foot having complementary apertures in the underside thereof located to receive said studs to position said plate with one edge aligned with said forward edge portion of said foot, two sets of upwardly facing cam surfaces on said flanges adjacent the respective ends of said foot, each set comprising a pair of said surfaces on the opposed sides of two adjacent iianges sloping upwardly toward the front of said foot and terminating in substantially horizontal flat portions, upstanding pins on said plate located to extend upwardly between said adjacent fianges above the level of said surfaces, a Washer fitted on each said pin for up-and-down movement thereon, stops limiting such movement toward said plate, a nut threaded on the upper end of each said pin, and a compression spring encircling each said pin and interposed between said nuts and washers, said washers being of suiiicient lateral extent to engage said respective sets of cam surfaces to compress said springs when said plate is moved forwardly closely beneath said foot and to hold said plate snugly against the underside of said foot when said washers reach such horizontal cam surface portions and said studs have entered the corresponding apertures in said foot.

2. In a paper cutting machine having a table, and a binder clamp adapted to bear forcibly upon a stack of sheets on said table to hold the same firmly in position and compressed during the cutting operation, said clamp including a presser foot member having a continuous forward edge portion and a series of rearwardly protruding flange fingers adapted thus to bear on such stack; a quickly removable false plate adapted to be secured to the underside of said foot to bridge said fingers and therefore bear more uniformly on such stack, and attaching means therefor comprising upstanding studs on said plate adjacent the respective ends thereof, said foot having complementary apertures in the underside thereof located to receive said studs to position said plate with one edge aligned with said forward edge portion of said foot, two sets of upwardly facing cam surfaces on said flanges adjacent the respective ends of said foot, each set comprising a pair of said surfaces on the opposed sides of two adjacent flanges sloping upwardly toward the front of said foot and terminating in substantially horizontal fiat portions, upstanding pins on said plate located to extend upwardly between said adjacent iianges above the level of said surfaces, a washer fitted on each said pin for up-anddown movement thereon, stops limiting such movement toward said plate, resilient means urging said washers toward said stop, said washers being of sufficient lateral extent to engage said respective sets of cam surfaces to be moved against the action of said resilient means when said plate is moved forwardly closely beneath said foot and to hold said plate snugly against the underside of said foot when said washers reach such horizontal cam surface portions and said studs have entered the corresponding apertures in said foot.

3. In -a paper cutting machine having a table, and a binder clamp adapted to bear forcibly upon a stack of sheets on said table to hold the same firmly in position and compressed during the cutting operation, said clamp including a presser foot member having a series of rearwardly extending fiange fingers adapted thus t0 'bear on such stack; ya quickly removable plate adapted to be secured to the underside of said foot to bridge said fingers and therefore bear more uniformly on such stack, and attaching means therefor comprising la plurality of upstanding projections on said plate, said foot having complementary apertures in the underside thereof adapted to receive said projections properly to position said plate, upwardly facing cam surfaces on said flanges located a substantial distance to each side of the vertical center line of said foot, said cam surfaces .sloping upwardly toward the front of said foot and terminating in substantially horizontal flat portions, and resilient clamping means mounted on the top side of said plate and located to engage said cam surfaces when said plate is moved forwardly closely beneathsaid foot and to draw and hold said plate snugly against the underside of said foot when said clamping means reach said horizontal cam surface portions and said` projections have entered said complementary apertures.

4. In a paper cutting machine having a table, and a binder clamp adapted to bear forcibly upon a stack of sheets on said table to hold the same firmly in position and compressed during the cutting operation, said clamp including a presser foot member having :a series of rearwardly extending flange fingers adapted thus to bear on such stack; a quickly removable plate adapted to be secured to the underside of said foot to bridge said fingers and therefore bear more uniformly on such stack, and attaching means therefor comprising upwardly projecting registering means on said plate adapted to fit in fa complementary recess in the underside of said foot, said foot having such recess adapted to receive said registering means, cooperating relatively vertically movable cam members on said foot and said plate 'adapted to interengage lower and upper surfaces respectively when said plate is moved forward closely beneath said foot, kand vertically operative resilient means adapted to urge said cam members together to draw said plate upwardly against the underside of said foot during such forward movement of said plate and resiliently :to secure said plate against the underside of said foot when said registering means reaches and lits in such recess.

5. In a paper cutting machine having a table, and a binder clamp adapted to bear forcibly upon a stack of sheets on said table to hold rthe same firmly in position and compressed during the cutting operation, said clamp including a presser foot member having a series of rearwardly extending flange ngers adapted thus to bear on such stack; Ia quickly removable plate adapted to be secured to the underside of said foot to bridge said fingers and therefore bear more uniformly on such stack, and attaching means therefor comprising complementary registering means on said plate :and foot adapted to determine the proper position of 'said plate, cooperating relatively vertically movable cam members on said foot and said plate ad-apted to interengage lower and upper surfaces -thereof when said plate is moved forward closely beneath said foot, and vertically operative resilient means adapted -to urge said cam members together to draw said plate upwardly against the underside of said foot during such forward movement of said plate and resiliently to secure said plate against the underside of said foot when said registering means reaches and ts in such recess.

6. In a paper cutting machine having a table, and a binder clamp adapted to bear forcibly upon a stack of sheets on said table to hold the same firmly in position and compressed during the cutting operation, said clamp including a presser foot member having a series of rearwardly extending flange fingers adapted thus to bear on such stack; -a quickly removable plate adapted to be secured to the underside of said foot to bridge said fingers and therefore bear more uniformly on such stack, and attaching means `therefor comprising cooperating cam members on said foot Iand said plate adapted to interengage lower and upper surfaces thereof when said plate is moved forward closely beneath said foot, and vertically operative resilient means `adapted to urge said cam members together to draw said plate upwardly against the underside of said foot.

7. The assembly of claim 6, and in which Vat least one of said cam members is inclined to atord increasing cornpression of said resilient means as said plate is thus moved forwardly.

References Cited inthe le of this patent UNTTED STATES PATENTS 1,028,919 Wadhams June 11, 1912 

